Dinosaur Feather Fossil Means T. Rex Cousin Had Plumage

LOS ANGELES — The discovery of a giant meat-eating dinosaur sporting a downy coat has some scientists reimagining the look of Tyrannosaurus rex.

With a killer jaw and sharp claws, T. rex has long been depicted in movies and popular culture as having scaly skin. But the discovery of an earlier relative suggests the king of dinosaurs may have had a softer side.

The evidence comes from the unearthing of a new tyrannosaur species in northeastern China that lived 60 million years before T. rex. The fossil record preserved remains of fluffy down, making it the largest feathered dinosaur ever found.

If a T. rex relative had feathers, why not T. rex? Scientists said the evidence is trending in that direction.

"People need to start changing their image of T. rex," said Luis Chiappe, director of the Dinosaur Institute at the Natural History Museum of Los Angeles County, who was not part of the discovery team.

Much smaller dinosaurs with primitive feathers have been excavated in recent years, but this is the first direct sign of a huge, shaggy dinosaur. Scientists have long debated whether gigantic dinosaurs lost their feathers the bigger they got or were just not as extensively covered.

The new tyrannosaur species, Yutyrannus huali, is described in Thursday's issue of the journal Nature. Its name is a blend of Latin and Mandarin, which translates to "beautiful feathered tyrant."

A team of Chinese and Canadian scientists analyzed three well-preserved fossil skeletons – an adult and two juveniles – recovered from a quarry in China's Liaoning province by a private fossil dealer. Most striking were the remains of down-like feathers on the neck and arm. Though coverage was patchy, scientists suspected the species had feathers over much of its body.

It would have felt like touching "long, thick fur," co-author Corwin Sullivan of the Chinese Academy of Sciences said in an email. Another scientist, Thomas Holtz Jr. at the University of Maryland, compared it to the feathers of an emu.

The creature lived about 125 million years ago. At 30 feet long and weighing a ton, Y. huali would have reached T. rex's chest.

The dino-fuzz likely provided insulation, though camouflage or showing it off like a peacock could not be ruled out.

Since T. rex is related to this newfound feathery species, chances are good that T. rex was feathered as well, scientists said. Just don't mistake fuzzy for cuddly. The predatory dinosaur would have been just as menacing.

Having feathers "doesn't make it less threatening or less fearsome," said Holtz, who had no role in the research.

Matthew Lamanna, assistant curator at the Carnegie Museum of Natural History, said T. rex most likely was covered in both feathers and scales.

Whatever the coverage of feathers, the latest fossil finds "force us to conceive of tyrannosauroids in a new way," said Julia Clarke at the University of Texas at Austin.

This North American bird, which stood over 8 feet tall, would have had an enormous, axe-like beak.

This heavily-armored predator had the second most powerful bite of any fish.

The hornless rhinoceros-like creatures of this genus were the largest land mammals of all time.

Giant ground sloths of this genus were about the size of today's elephants. The megatherium only went extinct around 10,000 years ago (right around the time when humans started farming), and smaller relatives may have survived as late as the 16th century!

Richard Owen, director of London's Museum of Natural History, stands next to the largest of all moa. Moa, which originated in New Zealand, were flightless, and some were even wingless.

The Argentavis magnificens, an early relative of the Andean Condor, was the largest flying bird ever discovered.

These creatures, the largest marsupials that ever lived, roamed Australia. Some scientists have suggested that stories of the supernatural 'bunyip' creature in Aboriginal folklore could be based on diprotodonts.

These distant relatives of modern elephants had an imposing appearance, with strange, downward-curving tusks and heights of up to 16 feet at the shoulder.

The fearsome Liopleuredon, right, had a jaw nearly ten feet long. The Leedsichthys, left, was a bony fish that may have been even larger than it looked; some estimates put its maximum length at 53 feet.
Correction: An earlier version of this slide had the positions of the Liopleuredon and Leedsichthys reversed.